SOME 2015-2017 TRANSIT VEHICLES MAY HAVE UNIQUE ACCESSORY DRIVE NOISE CHARACTERISTICS. ENGINEERING REVIEW OF WARRANTY RETURNED BELT TENSIONERS HAS NOT IDENTIFIED AN OUT OF SPECIFICATION PART, NOR HAVE ABNORMAL SOUNDS BEEN RECREATED DURING ON-VEHICLE EVALUATIONS WITH WARRANTY RETURNED TENSIONERS. BEFORE ATTEMPTING A REPAIR FOR AN ACCESSORY DRIVE SYSTEM NOISE, COMPARE THE SOUND TO A LIKE TRANSIT VEHICLE IN SIMILAR RPM AND TEMPERATURE CONDITIONS. IF THE SOUND IS NOT CHARACTERISTIC, USE CHASSIS EARS TO HELP ISOLATE THE SOURCE OF THE NOISE. IF TENSIONER REPLACEMENT IS DEEMED NECESSARY, USE THE REPORT A VEHICLE CONCERN LINK AT THE BOTTOM OF THE VEHICLE'S OASIS SCREEN AND SUBMIT A DETAILED GLOBAL CONCERN REPORT HIGHLIGHTING THE SPECIFIC CONDITIONS WHEN THE NOISE WAS OBSERVED.